What is wrong with my fish? please help?

the other day i cleaned out my fishes tank and i didn't do that thing where you hold the tub at the top of the water so the fishes can get used the water but i put them straight in, and i normally i would but i forgot this time, but one of the fishes dug up a little ditch in the corner with the pebbles/stones and it don't move or don't eat, my other fish pushes it in a non bullying way i think to try and help it , please help im really worried :/